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Physical Sciences Grade 12 P2 NSC November 2022 QP (Eng)

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Grade 12 Physical Sciences Paper 2 question paper from the NSC November Exam 2022 (English), 18 pages. Read online or download the free PDF.

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Downloaded from hlayiso.com NATIONAL SENIOR CERTIFICATE GRADE 12 PHYSICAL SCIENCES: CHEMISTRY (P2) NOVEMBER 2022 MARKS: 150 TIME: 3 hours This question paper consists of 14 pages and 4 data sheets. Copyright reserved Please turn over
Downloaded from hlayiso.com Physical Sciences/P2 2 DBE/November 2022 NSC INSTRUCTIONS AND INFORMATION 1. Write your centre number and examination number in the appropriate spaces on the ANSWER BOOK. 2. This question paper consists of NINE questions. Answer ALL the questions in the ANSWER BOOK. 3. Start EACH question on a NEW page in the ANSWER BOOK. 4. Number the answers correctly according to the numbering system used in this question paper. 5. Leave ONE line between two subquestions, e.g. between QUESTION 2.1 and QUESTION 2.2. 6. You may use a non-programmable calculator. 7. You may use appropriate mathematical instruments. 8. Show ALL formulae and substitutions in ALL calculations. 9. Round off your FINAL numerical answers to a minimum of TWO decimal places. 10. Give brief motivations, discussions, etc. where required. 11. You are advised to use the attached DATA SHEETS. 12. Write neatly and legibly. Copyright reserved Please turn over
Downloaded from hlayiso.com Physical Sciences/P2 3 DBE/November 2022 NSC QUESTION 1: MULTIPLE-CHOICE QUESTIONS Various options are provided as possible answers to the following questions. Each question has only ONE correct answer. Choose the answer and write only the letter (A–D) next to the question numbers (1.1 to 1.10) in the ANSWER BOOK, e.g. 1.11 E. 1.1 Which ONE of the following terms describes hydrocarbons that contain only single bonds? A Isomers B Saturated C Unsaturated D Homologous series (2) 1.2 Which ONE of the following combinations correctly indicates the STRONGEST intermolecular forces found in ethanoic acid and methyl propanoate respectively? ETHANOIC ACID METHYL PROPANOATE A Hydrogen bonds Hydrogen bonds B Dipole-dipole forces London forces C Hydrogen bonds London forces D Hydrogen bonds Dipole-dipole forces (2) 1.3 A test tube contains a liquid hydrocarbon. When bromine water (Br2) is added to the test tube, the mixture decolourises IMMEDIATELY. Which ONE of the following combinations correctly identifies the COMPOUND and the TYPE OF REACTION that takes place in the test tube? COMPOUND TYPE OF REACTION A Hexane Addition B Hexane Substitution C Hex-2-ene Addition D Hex-2-ene Substitution (2) Copyright reserved Please turn over
Downloaded from hlayiso.com Physical Sciences/P2 4 DBE/November 2022 NSC 1.4 Which ONE of the following statements is the CORRECT definition for the rate of a reaction? A The time taken for the reaction to take place B The speed at which the reaction takes place C The rate of change in concentration of the products or reactants D The rate of change in concentration of the products or reactants per unit time (2) 1.5 Consider the balanced equation for the reaction between magnesium powder and EXCESS dilute hydrochloric acid, HCℓ(aq): Mg(s) + 2HCℓ(aq) → MgCℓ2(aq) + H2(g) Which ONE of the following will NOT increase the rate of this reaction? A Increasing the volume of HCℓ(aq) B Increasing the temperature of HCℓ(aq) C Increasing the concentration of HCℓ(aq) D Adding more magnesium powder (2) 1.6 Two identical sealed gas jars, R and S, initially contain gases as shown below. 1 mole H2(g) + 1 mole I2(g) 2 moles HI(g) I2(g) I2(g) Gas jar R Gas jar S Equilibrium is reached in both gas jars at 500 °C according to the following balanced equation: H2(g) + I2(g) ⇌ 2HI(g) Which ONE of the following statements is TRUE at equilibrium? A S will contain 1 mole of I2(g). B R will contain a larger amount of I2(g) than S. C R and S will contain the same amount of HI(g). D S will contain a larger amount of HI(g) than R. (2) Copyright reserved Please turn over
Downloaded from hlayiso.com Physical Sciences/P2 5 DBE/November 2022 NSC 1.7 Which ONE of the following salts, when dissolved in water, will NOT change the pH of the water? A Na2CO3 B (COO)2Na2 C NH4Cℓ D NaCℓ (2) 1.8 A dilute acid is titrated against a potassium hydroxide solution, KOH(aq). At the equivalence point the pH is 7. Which ONE of the following combinations correctly identifies the acid and the MOST SUITABLE indicator for this titration? ACID INDICATOR A (COOH)2(aq) Phenolphthalein B (COOH)2(aq) Bromothymol blue C HCℓ(aq) Phenolphthalein D HCℓ(aq) Bromothymol blue (2) 1.9 Which ONE of the following statements is TRUE for an oxidising agent? A It gains electrons. B It causes another species in the reaction to be reduced. C Its oxidation number does not change during a chemical reaction. D Its oxidation number increases during a chemical reaction. (2) 1.10 Which ONE of the following metals will reduce Cd2+(aq) to Cd(s), but will NOT reduce Mn2+(aq) to Mn(s)? A Zn B Ag C Ni D Mg (2) [20] Copyright reserved Please turn over
Downloaded from hlayiso.com Physical Sciences/P2 6 DBE/November 2022 NSC QUESTION 2 (Start on a new page.) A to F in the table below represent six organic compounds. CH3 H CH3 C CH Br H C H A B H CH3 CH2 CH2 CH3 C C C C H CH3 CH3 H O O C CH3 CH2 CH2 C D CH3 CH2 C H CH3 O CH3 CH2 CH2 CH2 E CH3 CH2 CH2 C F OH OH 2.1 Write down the: 2.1.1 Letters that represent TWO organic compounds that are isomers of each other (1) 2.1.2 Type of isomers (CHAIN, FUNCTIONAL or POSITIONAL) identified in QUESTION 2.1.1 (1) 2.1.3 GENERAL FORMULA of the homologous series to which compound B belongs (1) 2.1.4 NAME of the functional group of compound F (1) 2.2 Write down the IUPAC name of: 2.2.1 Compound A (3) 2.2.2 Compound B (2) 2.2.3 Compound C (2) 2.3 Compound F reacts with a carboxylic acid to form compound S in the presence of a strong acid. 2.3.1 Write down the type of reaction that takes place. (1) Compound S has an EMPIRICAL FORMULA of C3H6O and a molecular mass of 116 g∙mol-1. 2.3.2 Write down the MOLECULAR FORMULA of the carboxylic acid. (3) [15] Copyright reserved Please turn over
Downloaded from hlayiso.com Physical Sciences/P2 7 DBE/November 2022 NSC QUESTION 3 (Start on a new page.) 3.1 The melting points of some organic compounds are given in the table below. COMPOUND IUPAC NAME MELTING POINTS (oC) A Propanone -95,4 B Butanone -86,9 C Pentan-2-one -77,8 D 3-methylbutanone -92 3.1.1 To which homologous series do the above compounds belong? (1) The melting points of compounds A, B and C are compared. 3.1.2 Write down the controlled variable for this comparison. (1) The melting points of compounds C and D are compared. 3.1.3 Fully explain the difference in the melting points of these two compounds. (4) 3.2 The table below shows the results obtained from an experiment to determine the vapour pressure of different STRAIGHT CHAIN primary alcohols at 300 K. ALCOHOL VAPOUR PRESSURE (kPa) CH3OH 16,8 C2H5OH 7,88 C3H7OH 2,8 C4H9OH 0,91 C5H11OH 0,88 C6H13OH 0,124 3.2.1 Define the term vapour pressure. (2) 3.2.2 Write down a suitable conclusion for this investigation. (2) 3.2.3 Write down the IUPAC name of the alcohol with the HIGHEST boiling point. (3) 3.2.4 The experiment is now repeated at 320 K. Will the vapour pressure of each compound INCREASE, DECREASE or REMAIN THE SAME? (1) [14] Copyright reserved Please turn over
Downloaded from hlayiso.com Physical Sciences/P2 8 DBE/November 2022 NSC QUESTION 4 (Start on a new page.) The flow diagram below shows how compound A can be used as a starting reactant to prepare two different compounds. I, II and III represent three organic reactions. Compound A I Compound B CH3C(CH3)BrCH2CH3 C5H10 (major product) II III Compound C C5H12O (major product) 4.1 Is compound A a PRIMARY, SECONDARY or TERTIARY haloalkane? Give a reason for the answer. (2) 4.2 Consider reaction I. 4.2.1 Besides heat, write down the other reaction condition needed. (1) 4.2.2 Write down the type of reaction that takes place. (1) 4.2.3 Using STRUCTURAL FORMULAE for the organic compounds, write down a balanced equation for the reaction. (5) 4.3 Consider reaction II. Write down the: 4.3.1 STRUCTURAL FORMULA of compound C (2) 4.3.2 NAME or FORMULA of the inorganic reagent needed (1) 4.3.3 Type of addition reaction that takes place (1) 4.4 Consider reaction III. 4.4.1 Write down of the type of reaction that takes place. (1) 4.4.2 Besides heat, write down the other reaction condition needed. (1) [15] Copyright reserved Please turn over
Downloaded from hlayiso.com Physical Sciences/P2 9 DBE/November 2022 NSC QUESTION 5 (Start on a new page.) Three experiments, A, B and C, are carried out to investigate some of the factors that affect the rate of decomposition of hydrogen peroxide, H2O2(ℓ). The balanced equation for the reaction is: 2H2O2(ℓ) → 2H2O(ℓ) + O2(g) Identical samples of hydrogen peroxide are used in each experiment. The conditions used in each experiment are summarised in the table below. EXPERIMENT TEMPERATURE (°C) A 25 Without catalyst B 25 With catalyst C 35 Without catalyst 5.1 In which experiment, A or B, is the reaction rate higher? Use the collision theory to explain the answer. (4) 5.2 The Maxwell-Boltzmann distribution curves, X and Y, for two of the above experiments are shown below. X Number of molecules Y Kinetic energy Identify the curve (X or Y) that represents experiment C. (2) Copyright reserved Please turn over
Downloaded from hlayiso.com Physical Sciences/P2 10 DBE/November 2022 NSC 5.3 The volume of oxygen gas, O2(g), produced in experiment B during the first 3,6 s is collected in a syringe, as shown below. 160 320 480 640 800 960 O2(g) 3 cm 5.3.1 Write down the volume of O2(g) collected in the syringe. (2) The balanced equation for the reaction is: 2H2O2(ℓ) → 2H2O(ℓ) + O2(g) 5.3.2 Calculate the mass of water, H2O(ℓ), that was produced during the first 3,6 s. Take the molar gas volume to be 24 000 cm3∙mol-1 at 25 °C. (4) 5.4 The graph below, NOT drawn to scale, is obtained for the mass of oxygen gas produced over a period of time in experiment A. 0,9 0,8 Mass of oxygen (g) 0,6 0,4 0 3 9 20 t 30 36 Time (s) Use the information in the graph to answer the following questions: 5.4.1 Write down the rate of production of oxygen gas for the interval 30 s to 36 s. (1) 5.4.2 Will the rate of the reaction in the interval 3 s to 9 s be GREATER THAN, SMALLER THAN or EQUAL TO the rate of the reaction in the interval 9 s to 20 s? (1) 5.4.3 The average rate of decomposition of hydrogen peroxide is 2,1 x 10-3 mol∙s-1. Calculate the value of time t on the graph. (5) [19] Copyright reserved Please turn over
Downloaded from hlayiso.com Physical Sciences/P2 11 DBE/November 2022 NSC QUESTION 6 (Start on a new page.) Carbon, C(s), reacts with sulphur, S(g), according to the following balanced equation: C(s) + 2S(g) ⇌ CS2(g) ∆H > 0 The system reaches equilibrium at temperature T in a sealed 2 dm3 container. The Kc value is 9,4 at temperature T. 6.1 State Le Chatelier's principle. (2) At equilibrium, 1 mole of carbon disulphide, CS2(g), is present in the container. 6.2 Calculate the concentration of S(g) present at equilibrium. (4) The volume of the container is now DOUBLED at temperature T. After a while, a NEW equilibrium is established. 6.3 How will the amount of S(g) change as this new equilibrium is established? Choose from INCREASES, DECREASES or REMAINS THE SAME. (1) 6.4 Explain the answer to QUESTION 6.3 in terms of Le Chatelier's principle. (3) 6.5 If the concentration of CS2(g) CHANGES by x mol∙dm-3, write down an expression for the equilibrium constant, Kc, in terms of x. Show ALL your workings. NO simplification or solving for x is required. (5) 6.6 The reaction rate-time graph below represents further changes made to the equilibrium mixture. The volume of the container is kept constant. Forward reaction Reverse reaction Reaction rate tA tB tC Time 6.6.1 What do the parallel lines between tA and tB represent? (1) 6.6.2 What change was made to the equilibrium mixture at tB? (1) 6.6.3 Give a reason for the sudden change in the reaction rate at tC. (1) 6.6.4 Fully explain the answer to QUESTION 6.6.3. (3) [21] Copyright reserved Please turn over
Downloaded from hlayiso.com Physical Sciences/P2 12 DBE/November 2022 NSC QUESTION 7 (Start on a new page.) 7.1 Ethanoic acid is a weak acid that reacts with water according to the following balanced equation: CH3COOH(aq) + H2O(ℓ) ⇌ CH3COO─(aq) + H3O+(aq) 7.1.1 Define an acid in terms of the Lowry-Brønsted theory. (2) 7.1.2 Give a reason why ethanoic acid is classified as a WEAK acid. (1) 7.1.3 Write down the formulae of the TWO bases in the equation above. (2) 7.2 A flask contains 300 cm3 of dilute sodium hydroxide, NaOH(aq), of concentration 0,167 mol·dm-3. 7.2.1 Calculate the number of moles of sodium hydroxide in the flask. (3) Ethanoic acid of volume 500 cm3 and of unknown concentration, X, is now added to this flask to give a solution of volume 800 cm3. It is found that the pH of the mixture is 11,4. The balanced equation for the reaction is: NaOH(aq) + CH3COOH(aq) → CH3COONa(aq) + H2O(ℓ) Calculate the: 7.2.2 Concentration of the OH─(aq) in the mixture (4) 7.2.3 Initial concentration, X, of the ethanoic acid solution (6) [18] Copyright reserved Please turn over
Downloaded from hlayiso.com Physical Sciences/P2 13 DBE/November 2022 NSC QUESTION 8 (Start on a new page.) 8.1 A piece of zinc (Zn) is placed in a test tube containing an acidified ─ permanganate solution, MnO (aq). After some time, it is found that a redox reaction has taken place. Use the Table of Standard Reduction Potentials to answer the following questions: 8.1.1 Write down the NAME or FORMULA of the reducing agent. (1) 8.1.2 Refer to the relative strengths of the OXIDISING AGENTS to explain why a redox reaction has taken place. (3) 8.2 A standard electrochemical cell is set up as shown below. V Ni Mn Y Ni2+(aq) Mn2+(aq) 8.2.1 Write down the function of component Y. (1) 8.2.2 In which direction will electrons flow in the external circuit? Choose from 'Ni to Mn' OR 'Mn to Ni'. (2) 8.2.3 Calculate the initial emf of this cell. (4) 8.2.4 Write down the balanced equation for the net cell reaction taking place. (3) 8.2.5 The concentration of Ni2+(aq) is now increased. Will the reading on the voltmeter INCREASE, DECREASE or REMAIN THE SAME? (1) [15] Copyright reserved Please turn over
Downloaded from hlayiso.com Physical Sciences/P2 14 DBE/November 2022 NSC QUESTION 9 (Start on a new page.) The diagram below represents a simplified cell used for the electrolysis of CONCENTRATED chromium(III) chloride, CrCℓ3(aq). Electrodes R and T are made of carbon. Battery R T Concentrated CrCℓ3(aq) The net cell reaction is: 2CrCℓ3(aq) → 2Cr(s) + 3Cℓ2(g) 9.1 Define the term electrolysis. (2) 9.2 The graph below, NOT drawn to scale, represents the changes in the mass of electrode T during electrolysis. X Mass of electrode T (g) 2,2 0 10 Time (hours) 9.2.1 Write down the half-reaction that takes place at electrode T. (2) A current of 2,5 A passes through the cell for 10 hours. Calculate the: 9.2.2 Total charge that flows through the cell during this time (3) 9.2.3 Value of X as shown on the graph (6) [13] TOTAL: 150 Copyright reserved
Downloaded from hlayiso.com Physical Sciences/P2 1 DBE/November 2022 NSC DATA FOR PHYSICAL SCIENCES GRADE 12 PAPER 2 (CHEMISTRY) GEGEWENS VIR FISIESE WETENSKAPPE GRAAD 12 VRAESTEL 2 (CHEMIE) TABLE 1: PHYSICAL CONSTANTS/TABEL 1: FISIESE KONSTANTES NAME/NAAM SYMBOL/SIMBOOL VALUE/WAARDE Standard pressure p 1,013 x 105 Pa Standaarddruk Molar gas volume at STP Vm 22,4 dm3∙mol-1 Molêre gasvolume by STD Standard temperature Standaardtemperatuur T 273 K Charge on electron e -1,6 x 10-19 C Lading op elektron Avogadro's constant NA 6,02 x 1023 mol-1 Avogadro-konstante TABLE 2: FORMULAE/TABEL 2: FORMULES m N n n M NA n m V c or/of c n V MV Vm ca a na pH = -log[H3O+] c n Kw = [H3O+][OH-] = 1 x 10-14 at/by 298 K Eθcell  Eθcathode  Eθanode / Eθsel  Ekatode θ  Eθanode or/of Eθcell  Ereduction θ  Eθoxidation / Eθsel  Ereduksie θ  Eθoksidasie or/of Eθcell  Eθoxidisingagent  Ereducing θ agent / E sel  Eoksideermiddel  Ereduseermiddel θ θ θ q = I∆t n = or/of n= e qe Copyright reserved Please turn over
Physical Sciences/P2 Downloaded from hlayiso.com 2 DBE/November 2022 NSC TABLE 3: THE PERIODIC TABLE OF ELEMENTS TABEL 3: DIE PERIODIEKE TABEL VAN ELEMENTE 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 (I) (II) (III) (IV) (V) (VI) (VII) (VIII) Atomic number 1 KEY/SLEUTEL Atoomgetal 2 2,1 H He 1 29 4 3 4 Electronegativity Symbol 5 6 7 8 9 10 1,0 1,5 1,9 Cu 2,0 2,5 3,0 3,5 4,0 Li Be Elektronegatiwiteit 63,5 Simbool B C N O F Ne 7 9 11 12 14 16 19 20 11 12 13 14 15 16 17 18 0,9 Na 1,2 Mg Approximate relative atomic mass 1,5 Aℓ 1,8 Si 2,1 P 2,5 S 3,0 Cℓ Ar 23 24 Benaderde relatiewe atoommassa 27 28 31 32 35,5 40 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 0,8 K 1,0 Ca 1,3 Sc 1,5 Ti 1,6 V 1,6 Cr 1,5 Mn 1,8 Fe 1,8 Co 1,8 Ni 1,9 Cu 1,6 Zn 1,6 Ga 1,8 Ge 2,0 As 2,4 Se 2,8 Br Kr 39 40 45 48 51 52 55 56 59 59 63,5 65 70 73 75 79 80 84 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 0,8 Rb 1,0 Sr 1,2 Y 1,4 Zr Nb 1,8 Mo 1,9 Tc 2,2 Ru 2,2 Rh 2,2 Pd 1,9 Ag 1,7 Cd 1,7 In 1,8 Sn 1,9 Sb 2,1 Te 2,5 I Xe 86 88 89 91 92 96 101 103 106 108 112 115 119 122 128 127 131 55 56 57 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 0,7 Cs 0,9 Ba La 1,6 Hf Ta W Re Os Ir Pt Au Hg 1,8 Tℓ 1,8 Pb 1,9 Bi 2,0 Po 2,5 At Rn 133 137 139 179 181 184 186 190 192 195 197 201 204 207 209 87 88 89 0,7 Fr 0,9 Ra Ac 58 59 60 61 62 63 64 65 66 67 68 69 70 71 226 Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu 140 141 144 150 152 157 159 163 165 167 169 173 175 90 91 92 93 94 95 96 97 98 99 100 101 102 103 Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr 232 238 Copyright reserved Please turn over
Downloaded from hlayiso.com Physical Sciences/P2 3 DBE/November 2022 NSC TABLE 4A: STANDARD REDUCTION POTENTIALS TABEL 4A: STANDAARD-REDUKSIEPOTENSIALE Half-reactions/Halfreaksies E θ (V) F2(g) + 2e ⇌ 2F + 2,87 3+  2+ Co +e ⇌ Co + 1,81 +  H2O2 + 2H +2e ⇌ 2H2O +1,77  MnO 4 + 8H + 5e 2+ ⇌ + Mn + 4H2O + 1,51   Cℓ2(g) + 2e ⇌ 2Cℓ + 1,36 2 Cr2O 7 + 14H + 6e 3+ ⇌ + 2Cr + 7H2O + 1,33 +  O2(g) + 4H + 4e ⇌ 2H2O + 1,23 MnO2 + 4H + 2e + 2+ ⇌ Increasing strength of oxidising agents/Toenemende sterkte van oksideermiddels Mn + 2H2O + 1,23 Increasing strength of reducing agents/Toenemende sterkte van reduseermiddels 2+  Pt + 2e ⇌ Pt + 1,20 Br2(ℓ) + 2e ⇌ 2Br + 1,07  +  NO 3 + 4H + 3e ⇌ NO(g) + 2H2O + 0,96 2+  Hg + 2e ⇌ Hg(ℓ) + 0,85 +  Ag + e ⇌ Ag + 0,80  +  NO 3 + 2H + e ⇌ NO2(g) + H2O + 0,80 3+  2+ Fe +e ⇌ Fe + 0,77 O2(g) + 2H + 2e + ⇌ H2O2 + 0,68   I2 + 2e ⇌ 2I + 0,54 Cu + e + ⇌ Cu + 0,52 +  SO2 + 4H + 4e ⇌ S + 2H2O + 0,45 2H2O + O2 + 4e ⇌ 4OH + 0,40 2+  Cu + 2e ⇌ Cu + 0,34 2 SO 4 + 4H + 2e ⇌ + SO2(g) + 2H2O + 0,17 2+  + Cu +e ⇌ Cu + 0,16 + 2e 4+ 2+ Sn ⇌ Sn + 0,15 +  S + 2H + 2e ⇌ H2S(g) + 0,14 2H + 2e + ⇌ H2(g) 0,00   0,06 3+ Fe + 3e ⇌ Fe + 2e  0,13 2+ Pb ⇌ Pb   0,14 2+ Sn + 2e ⇌ Sn + 2e  0,27 2+ Ni ⇌ Ni   0,28 2+ Co + 2e ⇌ Co + 2e  0,40 2+ Cd ⇌ Cd + e 2+  0,41 3+ Cr ⇌ Cr   0,44 2+ Fe + 2e ⇌ Fe + 3e  0,74 3+ Cr ⇌ Cr   0,76 2+ Zn + 2e ⇌ Zn 2H2O + 2e ⇌ H2(g) + 2OH  0,83   0,91 2+ Cr + 2e ⇌ Cr + 2e  1,18 2+ Mn ⇌ Mn   1,66 3+ Aℓ + 3e ⇌ Aℓ + 2e  2,36 2+ Mg ⇌ Mg   2,71 + Na + e ⇌ Na + 2e  2,87 2+ Ca ⇌ Ca Sr + 2e  2,89 2+ ⇌ Sr   2,90 2+ Ba + 2e ⇌ Ba + - Cs + e ⇌ Cs - 2,92   2,93 + K +e ⇌ K Li + e  3,05 + ⇌ Li Copyright reserved Please turn over
Downloaded from hlayiso.com Physical Sciences/P2 4 DBE/November 2022 NSC TABLE 4B: STANDARD REDUCTION POTENTIALS TABEL 4B: STANDAARD-REDUKSIEPOTENSIALE Half-reactions/Halfreaksies E θ (V) Li + e  3,05 + ⇌ Li K + e  2,93 + ⇌ K   2,92 + Cs + e ⇌ Cs + 2e  2,90 2+ Ba ⇌ Ba   2,89 2+ Sr + 2e ⇌ Sr + 2e  2,87 2+ Ca ⇌ Ca   2,71 + Na + e ⇌ Na + 2e  2,36 2+ Mg ⇌ Mg   1,66 Increasing strength of reducing agents/Toenemende sterkte van reduseermiddels 3+ Aℓ + 3e ⇌ Aℓ Increasing strength of oxidising agents/Toenemende sterkte van oksideermiddels + 2e  1,18 2+ Mn ⇌ Mn   0,91 2+ Cr + 2e ⇌ Cr 2H2O + 2e ⇌ H2(g) + 2OH  0,83 + 2e  0,76 2+ Zn ⇌ Zn   0,74 3+ Cr + 3e ⇌ Cr + 2e  0,44 2+ Fe ⇌ Fe  2+  0,41 3+ Cr +e ⇌ Cr + 2e  0,40 2+ Cd ⇌ Cd   0,28 2+ Co + 2e ⇌ Co + 2e  0,27 2+ Ni ⇌ Ni   0,14 2+ Sn + 2e ⇌ Sn + 2e  0,13 2+ Pb ⇌ Pb   0,06 3+ Fe + 3e ⇌ Fe 2H + 2e + ⇌ H2(g) 0,00 S + 2H + 2e + ⇌ H2S(g) + 0,14 4+  2+ Sn + 2e ⇌ Sn + 0,15 + e 2+ + Cu ⇌ Cu + 0,16 2 SO 4 + 4H + 2e ⇌ + SO2(g) + 2H2O + 0,17 + 2e 2+ Cu ⇌ Cu + 0,34   2H2O + O2 + 4e ⇌ 4OH + 0,40 SO2 + 4H + 4e + ⇌ S + 2H2O + 0,45 +  Cu + e ⇌ Cu + 0,52 I2 + 2e ⇌ 2I + 0,54 +  O2(g) + 2H + 2e ⇌ H2O2 + 0,68 + e 3+ 2+ Fe ⇌ Fe + 0,77  +  NO 3 + 2H + e ⇌ NO2(g) + H2O + 0,80 +  Ag + e ⇌ Ag + 0,80 2+  Hg + 2e ⇌ Hg(ℓ) + 0,85  +  NO 3 + 4H + 3e ⇌ NO(g) + 2H2O + 0,96   Br2(ℓ) + 2e ⇌ 2Br + 1,07 + 2 e 2+ Pt ⇌ Pt + 1,20 +  2+ MnO2 + 4H + 2e ⇌ Mn + 2H2O + 1,23 O2(g) + 4H + 4e + ⇌ 2H2O + 1,23 2 3+ Cr2O 7 + 14H + 6e ⇌ + 2Cr + 7H2O + 1,33   Cℓ2(g) + 2e ⇌ 2Cℓ + 1,36  MnO 4 + 8H + 5e 2+ ⇌ + Mn + 4H2O + 1,51 H2O2 + 2H +2 e + ⇌ 2H2O +1,77 + e 3+ 2+ Co ⇌ Co + 1,81 F2(g) + 2e ⇌ 2F + 2,87 Copyright reserved

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